This application supports the participation of the University of Chicago in Cancer and Leukemia Group B (CALGB) trials, including scientific and regulatory activities. The CALGB develops and performs clinical trials, primarily large scale clinical trials, to advance the treatment of cancer patients. The University of Chicago is a leading member of CALGB, supplying scientific and administrative leadership including the Group Chair (Dr Schilsky), Committee Chairs (Drs Ratain, Vokes, and Larson), and Study Chairs. Preliminary studies performed at the University of Chicago are taken to CALGB for large scale testing. Laboratories at the University of Chicago perform correlative studies that support CALGB trials. University of Chicago senior faculty mentor junior faculty and fellows in cooperative group participation, with large meeting attendance and eight CALGB Foundation grants awarded to University of Chicago fellows and junior faculty during the past granting period. In addition, The University of Chicago and its eight affiliate institutions are consistently among the top five accruers to CALGB studies with broad participation across all tumor types and substantial minority accrual.